CONTRA COSTA COUNTY (KRON) — Authorities have made six arrests in connection with three armed robberies in the East Bay, officials announced Tuesday.

FBI Safe Streets Task Force worked with local law enforcement agencies including the Contra Costa County District Attorney’s Office to make the arrests.

The arrests are in connection to three home invasion robberies that happened in Danville, Livermore, and Fremont.

Contra Costa County Deputy District Attorney Barry Grove said the mode of operation was similar in these crimes.

“Well, they’re home invasion robberies,” Grove said. “So, a group of people go into a house armed with guns and attempt to rob the residence inside the house.”

Grove said the six adult male suspects were arrested on charges that include home invasion, robbery, burglary, and a carjacking case last week on Conejo Drive in unincorporated Danville.

Investigators are checking for any connections between these suspects and last week’s shooting and robbery of Carol Brown and her husband in the driveway of their home in Orinda

It is an investigation getting some back up from federal law enforcement

“The FBI and the district attorney’s office have a Safe Streets Task Force that was put together a couple of years ago,” Grove said. “This has been some excellent work in a long-term, ongoing investigation, and hopefully, we will solve more cases in the next week or so.”

Authorities previously announced that they believed that that several armed robberies throughout Contra Costa County are connected.